TLS hostname verification failed for hostname: shibboleth.net

[McLennan, Neil R]

I am running Windows Shibboleth IDP4 version 4.2.1  
When I run 
plugin.bat -I net.shibboleth.idp.plugin.oidc.op
ERROR  -  Could not load update URL javax.net.ssl.SSLPeerUnverifiedException: TLS hostname verification failed for hostname: shibboleth.net

I have tried to add the certificate from https://shibboleth.net/downloads/identity-provider/plugins/plugins.properties to the java keystore but still unable to get plugin.bat to work.
keytool -genkey -alias server2  -keyalg RSA -keystore -cacerts -file shibboleth.net.pem

Is there a way to ignore TLS hostname verification ?

Neil